Gas-pump.



w No. 742,940. PATENTED NOV. 3, 1903.

R. WHITAKER.

GAS PUMP.

APPLICATION FILED 001.. 14, 1902.

30 MODEL.

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No. 742,s4o.

UNITED STATES Patented November 3, 1903.

PATENT OFFICE.

RICHARD WHITAKER, OF NEW BRUNSWICK, NEW JERSEY, ASSIGNOR OF TWO-THIRDS TO ROBERT W. JOHNSON AND JAMES W. JOHNSON, OF

NEW BRUNSWICK, NEW JERSEY.

GAS-PUMP.

SPECIFICATION forming part of Letters Patent No. 742,940, dated November 3, 1903. Application filed October 14,1902. Serial No. 127.230. (No model) To all whom it may concern.-

Be it known that I, RICHARD WHITAKER, a citizen of the United States, residing at New Brunswick, in the county of Middlesex and State'of New Jersey, have invented certain new and usefullmprovementsin Gas-Pumps, of which the following is a specification.

This invention relates to air or gas pumps and valves thereof operating on a suitable IO fluid, the object of which is to provide means for reducing the area on the back of the discharge-valve which can be acted on by the discharge-pressure, the invention being shown in the accompanying drawing, which reprel5 sents a vertical central section through the valves of a portion of a pump constructed in accordance with my invention.

In said drawing, A represents the valvecylinder, which has in its interior a valveseat, which consists,preferably,of asteel ring 2 to obtain a smooth and hard surface. Said ring rests upon an annular shoulder 3,formed in the interior of the cylinder above the piston-chamber 4. The valve-cylinder is bored 2 5 above the ring 2 to fit the periphery of the lower portion of the discharge-valve C; but the upper portion of the interior of the cylinder is formed by the pendent cylindrical flange of the coverB and is of smaller diam- 0 ete'r to fit the periphery of the upper portion of the valve 0, the bottom of said flange forming an annular shoulder 8, there being also an annular shoulder 5 around said valve between its upper and lower portions. This annular shoulder 5 represents the difference in area between the upperandlowersurfaces of the valve 0 exposed to discharge-pressure, and the pressure of the gas upon the shoulder 5 helps the spring R, so that a spring of less 0 power can be used to keep the valve 0 closed,

while said pressure on the shoulder 5 is removed by suction through the pipe 12 at-the time the piston Q ascends, and the pressure of said piston upon the gas above it slightly lifts and opens the valve 0. The head B of the cylinder is suitably attached to the body of the pump and has a pendent cylindrical flange that fits also the periphery of the upper portion of the valve C. Around the periphery of the upper portion of said valve there are packing-rin gs 6 and around its lower portion are packing-rings 7 of suitable construction.

Within the wall of the cylinder A about half-way of the length of the discharge-valve O there is an annular suction-chamber K, which is protected from the discharge-pressure on both its top and bottom by the packing-rings 6 and 7; but discharge-pressure is admitted on top of the valve 0 through a passage S, formed in the body of the valve 0, from the bottom discharge-chamber L of the pump-cylinder.

Within the hollow of the valve 0 is placed acoiled spring R of predetermined strength according to the pressure intended to be exerted. One end of said spring bearing against .the under side of the head B of the cylinder and the other end upon the bottom portion of the discharge-valve G acts to seat said valve against the discharge-pressure acting on the under side of said valve.

Within the lower portion of the cylinderA is placed the piston Q. The chamber 4 below the piston is used as a receiver for the 7 sucked-in fluid, (which may be air, gas, or liquid.) This chamber 4 is in communication with the suction-chamber K by means of the pipe 12 alongside of the cylinder. The piston Q is hollow, and its top is provided with a valve-seat q, upon which is seated the conical suction-valve D. Said valve has a stem E,which is received in and guided by a spiderboss Q forming a part of the piston Q. Upon the stem E is mounted a broad head e, 8 fastened to the stem by nuts e A coiled spring H is placed between the boss Q and the head 6 to cause the suction-valve D to remain normally upon its seat q. The fluid passes from the lower chamber 4 under the ho piston, through the opening shown closed by the valve D,into the chamber above said valve when the latter is opened. When the fluid is compressed by the piston Q, the dischargevalve 0 is raised and lets the fluid directly into 5 the chamber L and out through the pipe M.

The function of the chamber K is to supply suction fluid-pressure onto the small annular shoulder 5 of the discharge-valve. This shoulder is protected from the heavier disroo 6. The passage S, or a series of them, admits the discharge-pressure to the entire back of the discharge-valve, except the small area of the shoulder 5, which has upon it the suctionpressure only. Consequently when the valve 0 is standing open the entire bottom of said valve is exposed to the discharge-pressure acting upward and a portion of the top of the valve is exposed to the discharge-pressure acting downward and the area of the shoulder 5 is exposed to suction-pressure acting downward. The suction-pressure being m uch less than the discharge-pressure, the valve is supplied with the pressure of the spring R, which is enough to seat the valve. The pressure against which the valve 0 will close is regulated by the predetermined strength of the spring R or by the amount of the width or area of the annular shoulder 5, or by both of said means together, thuslimiting the pressure to which the pump can force a fluid into a receiver.

Having now fully described my invention, I claim 1. Thecombination ofavalve-cylinder havingin its interior an annular shoulder 8 dividing it into two chambers of different diameters, and having an annular chamber K in communication with said shoulder, and a discharge-chamber on a lower level, a valve-seat alongside of the discharge-chamber, a spring having its upper end bearing against the under side of the top of the valve-cylinder and its lower end pressing upon the top of the discharge-valve, and under said discharge-valve a cylinder forming a chamber 4, a piston, and a spring-Valve seated within said piston, substantially as described.

2. The combination ofavalve-cylinderhaving in its interior an annular seat for a discharge-valve, said discharge-valve having a shoulder around its periphery, a chamber K within the walls of the cylinder and in communication with said shoulder, a dischargechamber encircling the bottom of the discharge-valve and under said discharge-valve a cylinder forming a chamber 4, and within said chamber a piston having a spring-valve seated therein, and a pipe connecting the chamber under the piston with the chamber K, substantially as described.

3. Thecombination ofavalve-cylinderhav ing an annular chamber K and also a discharge-chamberin its walls, adischarge-valve having an annular shoulder in communication with the chamber K, the bottom of the discharge-valve being adapted while lifted to be in communication with the dischargechamber, a cylinder forming a chamber 4, a

piston under the discharge-valve, a springvalve seated within said piston and a passage from under the piston to the chamber surrounding the shoulderon the discharge-valve, substantially as described.

In testimony whereof I aflix my signature in presence of two witnesses.

RICHARD WHITAKER.

Witnesses:

GEO. F. MCCORMICK, FRANK E. FISHER. 

